I personally would not use these hooks on the marine fabric. The core weave/threads of the material would weaken and there goes your coffee mug or what have you, dangling by a thread. Not enough substrate to adhere to. Furthermore, I wouldn't want to thin out or otherwise cause a bare area in the marine fabric from the repeated stress of trying to hold something up.
I have those hooks on my fridge
door and find that suction cup hooks have worked well on FG interior for other little doo dads.
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